Cutting tool



Patented Sept. 30, 1947 CUTTING Toot Y Lawson Allen Smith, Los Angeles,Calif, assignor I to Robert H. Clark, Los Angeles, Calif, I Originalapplication February 18-, l9 44, Serial No.

522,901. Divided and this application January 19, 1945, Serial No..573,597 t i l 11 Claims.

This invention has to do with a cutting tool and has particularreference to that type of tool used in performing the operation commonlyknown as spot facing or counterboring.

In the manufacture of various machine parts or devices it is frequentlydesired to finish or machine a surface inthe immediate vicinity of oraround a bore. Devices known as counterbores or spot lacers are used forthis purpose, it being common to provide such devices with pilots thatenter the bore and with blades that act to cut the surface desired. Acommon difficulty with such tools is that a burr is formed at the pointof joinder of the surface and hole, with the result that the toolbecomes stuck or fails to operate smoothly. With most tools of thegeneral character referred to it is not at all uncommon for the pilotsto become stuck, causing considerable inconvenience and often damage.

It is a general object of this invention to provide a tool with a formof cutter that will effectively spot face or counterbore. The tool ofthe present invention involves a cutter with a shank portion that can beangularly disposed to be advantageously held by the body of the toolwhile the tip portion is pitched in any desired manner, say forinstance, at right angles to the axis of the tool, to perform thedesired cut, the tip portion being in the form of a. depending ex-'tension on the shank suitable to be dressed in any desired manner.

Another object of the present invention is to provide an improved meansfor retaining the pilot in the tool. In the preferred form of theinvention the blades cooperate with the stem of the pilot to retain thepilot in the body.

This application is filed as a division of my co-pending applicationentitled Cutting tool, filed February 18, 1944, Serial No. 522,901. l

The various objects and features of my invention will be fullyunderstood from'the following detailed description of a typicalpreferred form and application of the invention, throughout whichdescription reference is made to the accompanying drawings, in which:

Fig. l is a side elevation of a tool embodying the present invention,being a view taken in a direction to show the forward or leading side ofone of the blades of the tool. Fig. 2 is a view similar to Fig. 1 takenwith the tool rotated through 90. Fig. 3 is a bottom end view of thetool of the present invention, being a view taken as indicated by line33 on Fig. 1, and Fig.4 is a central, sectional view of the tool showingthemanner in which the blades act to retain the shank of the pilot inthe body d The tool of the present invention'embodies, generally, a bodyI0, a shank II- on the 'body for mounting 'it-in a machine of suitablecharacter, blades I2 carried by the body to project from the V ,2 lowerend thereof, means I3 operable to clamp the blades'in the desiredposition on the'body, and a pilot I4 carried by the body to project fromthe lower end thereof and to cooperate with blades I2 tomakethe desiredcut. A feature of the construction provided by my present invention isthe elimination of separate or independent means. for retaining thepilot It in position. In the usual'tool of the character underconsideration a set screw, screw thread, or other mechanical'meansisfprovided to retain the pilot or to retain a stem carrying thepilot, so that the pilot or its'stem will not become detached from thebody Ill. By my present invention I eliminate entirely any special meansfor this purpose but effectively retain the pilot in the desired po-"with the body to project from the upper end thereofand is'proportioned, shaped and finished to be accommodated in-a suitable toolor operating machine. In the particular form of the inventionillustrated-the shank is shown round in 7 to be carried by-the' body Illto project from the lower end thereof, the lower end portion of eachblade being dres's'ed'or sharpened to have the desiredcuttin-g' action.In the preferred form of the invention the lower end I? of the body isflat so that it lies in aplane transverse to the' longitudinal aXis-of-the tool, and the cutters are carried by the-body to project fromthe lower end II thereof.

In practice I provide'the tool with tWo blades I2 and I locatethe-blades-diametrically opposite each other,*or at opposite sides ofthe body In. In the general arrangement clearly illustrated in thedrawings, the body II) has channels I8 out in diametrically oppositesides to carry the blades Ill. The channels are of sufficient width toslidably pass the'blades and are made sulfici'ently deep so that theblades are well seated in the body to be firmly supported thereby. Bymaking the-channels deep the bottoms I9 of the channels are considerablywider, or of greater area, than they would be if the channels wereshallow, this being due to the fact that the body' 3 is hexagonal incross-section, and the surfaces I!) become wider as the. channels aredeeper- In the preferred form of the invention I pitch or incline thechannels l8 so the blades are carried to extend downward and outwardfrom the; lower end I! of the body, that is, the channels are angularlydisposed or pitched to carry the shank portions A of the cutters. sothat. they ex-- tend down and out, while the blade portions B of thecutters depend from the lower ends of the shanks to project below theend H of the body in the desired manner. I not onlyform the blades todepend from the shanks, but I ofiset them rearwardly, as shown in thedrawings, par-v ticularly Fig. 2, so thatthey fit into the notched pilotin a most advantageous manner. By rearwardly cfisetting the blades the:body can be. of substantial size and the bladesspaced a ccnsiderabledistance apart, and yet. 1 am able to. employ a. pilot of small diameterand at the. same time have the cutting e ges of the blades. overlap thesurface of the pilot. It is, to be understood that the channels arepitched to. correspond to each other, so that the blades or'thelr shanksare carried at corresponding. angles. and that the angles are such that.the channels extend a considerable distance upward. in the. body fromthelower end thereof to give the shanks. of. the: blades. adedilatesupport.

The shank portions A of the blades are. pref: erably rectangular incrossesection to. occupy the channels in the mannerillustratedinthedrawings, and the upper ends 611 oi the shanks are cuton parallel with the axis of. the. tool,

The blade. portion 13 of; each cutter depends from the outer or lowerendportion of the shank and-it is shaped andproportioned to best suitthe work to be performed. A feature of the pres ent invention is theprovision or a. distinct blade portion on the lower or outer end. of theshank, which blade portion dependsfrom the shank and is adapted tobedressed or finished inany dc. siredmanner to accomplish-any 59 .1. ofcutting action. In the drawings-- I show a blade, designed to spot faceand, consequently; the; blade is shapedsc hat it is disposed at r ght-anl s; o. the axis of: the, tool and has a horizontally dis, posed cuttingedge. 20-, The outer; side, or edge. portion- Zll of the, blade;- ispreiierably: dressed or rounded to give desired: clearance, and in:corresponding manner the; lower end ZBP of the blade shank iscorrespondingly dressed or. rounded; as clearly shownin the drawings,I-t.is;to;-be:understood, of course, that suitable clearance isprovided'immediatelybeh-ind the? euttingredge 20 or each blade by suitablydressing the bottom 20 f. theblade. In. practice the. blade ma-ybedressed so that its cutting edge isdisposedai any suitable anglerelatitve to the: axis or the; tool. In. the particular tool illustratedthe. edge; extends tangentially to a circle concentric with the. axisof'the tool, to give thetool ashearingi cticrr desired for theparticular work. to be; performed. It isto. be understood that: the:front. face 21' of the, blade can be: suitably: dressed" or: shaped toprovidev chip clearance or to. direct: cuttings so that the tool; doesnot become clogged in the course of operation,

The mean l-3 providedfcr holding the, blades in. place in the; channelsk8 of-themay be any suitable means thatrwillserver this function.

In the construction. illustrated I provide clam-p plates 25-toengagethe. outer sides ot, the: shanks A and I provide; cap SCIEWS 25-to extend: through 4 the body Hi. The plates are washer-like memhers.that overlap or overhang the shanks of the cutters while the cap. screwsare preferably of the hollow head type.

The pilot 14 may be of any desired construction, that is, it may be abuilt up structure such as is illustrated in the parent applicationhereinabove referred to, or it may be a simple guide pin, such. as isshown in the drawings. In accordance with my present invention the stemportion 30 of the pilot slidably fits into a bore 3| provided in thecenter of the body from its lower end l-T, while the tip or head 32 ofthe pilot is of, any desired diameter and projects below the end I! ofthe body to enter a guide hole or bore in which the tool is operated.In. the particular caseshown in the drawings. thestem, portion, 30 andworking portion 32 of the pilot are of the same diameter, In accordancewith my present invention the pilot is retained in the bore 3| providedin. the. body through engagement by-one or both of the blades l2. In theparticular armngement. illustrated the pilot is held by both blades. Bymy present invention Iv proportion the grooves. l8. which carry theshanks A of the cutters so, that. they extend deep into the body or,atleast, deep. enough into-the body to intersect. the bore 3i, so thatwhen. the cutters are seated the grooves. or channels I8 the. innersidesof the shank, portion .A. are in or intersect the. bore. In orderthatthe parts may properly cboperateand that thev stem of the pilot beheld by the blades I provide. recesses or notches 40- in the sides ofthe stem. 30. to accommodate the shanksA of the blades. In practice theparts can bepropcrtiened so that the recesse 40 are shal- IQW, that is,so that there is butslightoverlap'or interengagement or. the cutterswith the pilot, as ity is merely necessary that there besome engagementbetween these parts in order to effect proper retention of the pilot. Insome cases the arrangement. may be such that; the cutters have pressureengagement with the: stem of the pilot, without beingv actuallyrecessedz therein.

A feature of the. construction that I have pro.- vided is that thecutting edges 20. of the cutter blades B overlap the surface of the head32. of the pilot. To accomplish this-the head 32- ot the pilot-isnotched at' .0. and. the notches 55 extend far enough below the end I!of the body sothatthe blade portions B of the cutters nest or fit intothem, that is, the inner end portions of the blades fit, intothe notches50. The notches are preferably made large enough so that there issomeroom for movement or a justment ofthe bladestherei-n.

Where the construction involves two diametrically opposite blades I-.2there are two diametri callyopposite. notches. 40. in the, stem. 3a. ofth pilot and, likewise, two diametrically opposite.

- the pilot. However; in practiceI prefer to eliminatethis, elemententirely since the direct engagement-oithecutters with the stem ofthepilot is a most efiective means for holding the pilot and anysupplemental means, such as the set screw Til, is entirely unnecessary;

From the foregoing. descriptionit will be apparentthat I have providedav cutter that is extremely simple and inexpensive of manufacture and.which provides cutters l2 having shanks apthe plates and thread into:tapped openings; in 5 plieq tolthe body Ill inamost advantageous manner,at the same time having blade parts B shaped and disposed to cut in amost advantageous manner, in fact, to cut any form of cut that may bedesired. It is also to be noted that when the cutters l2 are secured tothe body ill by the means l3 they intersect thebore 3| that carries thestem of the pilot, so that parts of the shanks A engage in the notches40 ofthe pilot and thus effectively'andpositively retain'the stem- 30 ofthe pilotinthe bore 3|-.""-"- 1 :It 'i s to'be'understood that theconstruction that I have provided permitsof-cutters with'various shapedblades being used; and also that pilots with heads 32 of various sizescan be employed.

In any particular tool the shank r stem portion of the pilot provided tofit the bore 3| will be of a size to properly fit the bore and will beprovided with notches 40 to accommodate the cutters which serve not onlyas cutters, but as the means for retaining the shank or stem of thepilot in place in the body.

Having described only a typical preferred form and application of myinvention, I do not wish to be limited or restricted to the specificdetails herein set forth, but wish to reserve to myself any variationsor modifications that may ap pear to those skilled in the art and fallwithin the scope of the following claims.

Having described my invention, I claim:

1. A tool of the character described including, a body having a centralsocket in its lower end and having a channel laterally offset from theaxis of the socket, a cutter retained in the channel to have a cuttingedge located beyond the lower end of the body, and a pilot carried bythe body with a surface to fit a hole and continuing from a point abovesaid edge to a point below said edge, the pilot including a stem carriedin the socket of the body and a head on the stem having the saidsurface, the cutter being carried by the body to engage a side notch inthe stem to hold the stem tight in the body.

2. A tool of the character described including a body an angularlydisposed channel in one side with a bottom in a plane tangent andparallel to the body and pitched to extend lengthwise and sidewise ofthe body to open at the lower end of the body, a cutter carried by thechannel and having a rearwardly offset lower cutting end beyond thelower end of the body with a forwardly facin cutting edge, and a pilotcarried by the body overlapping the edge.

3. A tool of the character described including a body having a centralsocket and a side channel, a cutter carried by the channel and having arearwardly offset lower cutting end with a forwardly facing cuttingedge, and a pilot carried by the socket overlapping the edge, the pilothaving a notch confined to its side and receiving the inner end portionof said edge.

4. A tool of the character described including, a body having a centralsocket and a side channel in it having a bottom in a plane offset fromthe axis of the body and intersecting the socket, a cutter retained inthe channel with one side bearing on the bottom of the channel andhaving a cutting edge extending at substantially right angles to thelongitudinal axis of the tool and located beyond the lower end of thebody, and a pilot carried by the body with an outer surface concentricWith the axis of the tool to fit end of the bodygand a pilot carried bythe body with an outer surface concentric with the axis of the tool tofit a holeand continuing froma pointabove said edge to a point belowsaid edge, there being aside notch inthe'pilotso' that the inner endportion of sai'dedge is spaced from and overlaps said surface therebeing a second side-notch in the pilot receivin the cutter so the pilotis retained by the cutter.

6. A tool of the character described including, a body having a sidechannel in it remote from the center of the body and extendinglengthwise and sidewise of the body to its lower end, a cutter carriedby the channel to have a cutting edge disposed tangent to a circleconcentric with the central axis of the tool and located beyond thelower end of the body, and a pilot carried by the body with a curvedsurface concentric with the central axis of the tool and of largerdiameter than said circle to fit a hole and continuing from a pointabove said edge to a point below said edge, the body having a centralbore receiving the pilot and intersecting the channel so the cutterengages and retains the pilot.

7. A tool of the character described includin a body having a channelconfined to one side thereof, a cutter carried by the channel and havinga rearwardly oifset lower cutting end with a forwardly facing cuttingedge, means clamping the cutter toward the center of the body to hold itin the channel, and a pilot carried by a central bore in the body thatintersects the channel and overlapping the edge, the cutter engaging thepilot in the bore to retain the pilot therein.

8. A tool of the character described including, a body having a channelin it and confined to one side thereof, a cutter carried by the channelto have a cutting edge located beyond the lower end of the body, clampmeans carried by said side of the body engaging the outer side of thecutter and holding the cutter in the channel, and a pilot carried by thebody with a surface to fit a hole and continuing from a point above saidedge to a point below said edge, the pilot including a stem carried in acentral socket in the body and a head on the stem having the saidsurface, the inner side of the cutter engaging one side of the stem tohold the stem in the socket in the body.

I have a cutting edge located beyond the lower a hole and continuingfrom a point above said end of the body, clamp means carried by saidside of the body engaging the outer side of the cutter and a pilotcarried by the body with a surface to fit a hole and continuing from apoint above said edge to a point below said edge, the pilot includingstem carried in a central socket in the body and a head on the stemhaving the said surface, the stem having a side notch and the cutterbeing carried by the body to engage the notch in the stem to hold thestem in the body.

10. A tool of the character described including a body with channelsconfined to opposite sides thereof, and a central bore in it from itslower end and intersecting the channels, a pilot having a stem in thebore, cutters carried in the channels to engage the pilot at oppositesides and having cutting edges below the end of the body,

